Abstract:
The dynamic nature of species and energy exchanges during electrocatalysis indicates that the electrochemical interface must not be an abrupt boundary between the catalyst and electrolyte, instead, is a broadened active region that encompasses intricate interactions. The diverse behaviors are thus a result of the intricate interactions at the solid-liquid interface, in which the interfacial features are highly relevant. In the past years, numerous studies have highlighted the significant roles of catalyst structures and electrolyte effects on activity/selectivity, however, their dynamic behaviors and essential relevance of all aspects at the solid-liquid interface under working conditions are currently far from being completely understood. Especially, the dynamic behaviors of electrocatalysts makes the working electrochemical interface even more complicated, thus the atomic-level understanding of interfacial dynamic configurations for providing unprecedented insights is still missing. In this regard, X-ray absorption spectroscopy has become one of the most popular techniques for providing fruitful information regarding the dynamic structure of electrocatalysts with poor crystalline nature, in which X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra are capable of offering informative features about the electronic and geometric structures of target atoms. Additionally, multiple in-situ approaches, including non-resonant X-ray emission spectroscopy (XES) and resonant inelastic X‐ray scattering (RIXS), have been brought to bear to offer a comprehensive understanding of the precise reactive-configuration of electrocatalysts.